gtk2/gdk/gdkframeclock.c
Matthias Clasen 4c2761302a doc: Syntax fixes
No, we can't have links that say [constructor@...] or
[mehtod@...] or [methoc@...] or [methos@...] or [metohd@...].
And no, not [signals@...] either.
2021-05-25 07:33:55 -04:00

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/* GDK - The GIMP Drawing Kit
* Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
/*
* Modified by the GTK+ Team and others 1997-2010. See the AUTHORS
* file for a list of people on the GTK+ Team. See the ChangeLog
* files for a list of changes. These files are distributed with
* GTK+ at ftp://ftp.gtk.org/pub/gtk/.
*/
#include "config.h"
#include "gdkframeclockprivate.h"
#include "gdkinternals.h"
/**
* GdkFrameClock:
*
* A `GdkFrameClock` tells the application when to update and repaint
* a surface.
*
* This may be synced to the vertical refresh rate of the monitor, for example.
* Even when the frame clock uses a simple timer rather than a hardware-based
* vertical sync, the frame clock helps because it ensures everything paints at
* the same time (reducing the total number of frames).
*
* The frame clock can also automatically stop painting when it knows the frames
* will not be visible, or scale back animation framerates.
*
* `GdkFrameClock` is designed to be compatible with an OpenGL-based implementation
* or with mozRequestAnimationFrame in Firefox, for example.
*
* A frame clock is idle until someone requests a frame with
* [method@Gdk.FrameClock.request_phase]. At some later point that makes sense
* for the synchronization being implemented, the clock will process a frame and
* emit signals for each phase that has been requested. (See the signals of the
* `GdkFrameClock` class for documentation of the phases.
* %GDK_FRAME_CLOCK_PHASE_UPDATE and the [signal@GdkFrameClock::update] signal
* are most interesting for application writers, and are used to update the
* animations, using the frame time given by [method@Gdk.FrameClock.get_frame_time].
*
* The frame time is reported in microseconds and generally in the same
* timescale as g_get_monotonic_time(), however, it is not the same
* as g_get_monotonic_time(). The frame time does not advance during
* the time a frame is being painted, and outside of a frame, an attempt
* is made so that all calls to [method@Gdk.FrameClock.get_frame_time] that
* are called at a “similar” time get the same value. This means that
* if different animations are timed by looking at the difference in
* time between an initial value from [method@Gdk.FrameClock.get_frame_time]
* and the value inside the [signal@GdkFrameClock::update] signal of the clock,
* they will stay exactly synchronized.
*/
enum {
FLUSH_EVENTS,
BEFORE_PAINT,
UPDATE,
LAYOUT,
PAINT,
AFTER_PAINT,
RESUME_EVENTS,
LAST_SIGNAL
};
static guint signals[LAST_SIGNAL];
static guint fps_counter;
#define FRAME_HISTORY_MAX_LENGTH 16
struct _GdkFrameClockPrivate
{
gint64 frame_counter;
int n_timings;
int current;
GdkFrameTimings *timings[FRAME_HISTORY_MAX_LENGTH];
int n_freeze_inhibitors;
};
G_DEFINE_ABSTRACT_TYPE_WITH_PRIVATE (GdkFrameClock, gdk_frame_clock, G_TYPE_OBJECT)
static void
_gdk_frame_clock_freeze (GdkFrameClock *clock);
static void
gdk_frame_clock_finalize (GObject *object)
{
GdkFrameClockPrivate *priv = GDK_FRAME_CLOCK (object)->priv;
int i;
for (i = 0; i < FRAME_HISTORY_MAX_LENGTH; i++)
if (priv->timings[i] != 0)
gdk_frame_timings_unref (priv->timings[i]);
G_OBJECT_CLASS (gdk_frame_clock_parent_class)->finalize (object);
}
static void
gdk_frame_clock_constructed (GObject *object)
{
G_OBJECT_CLASS (gdk_frame_clock_parent_class)->constructed (object);
_gdk_frame_clock_freeze (GDK_FRAME_CLOCK (object));
}
static void
gdk_frame_clock_class_init (GdkFrameClockClass *klass)
{
GObjectClass *gobject_class = (GObjectClass*) klass;
gobject_class->finalize = gdk_frame_clock_finalize;
gobject_class->constructed = gdk_frame_clock_constructed;
/**
* GdkFrameClock::flush-events:
* @clock: the frame clock emitting the signal
*
* Used to flush pending motion events that are being batched up and
* compressed together.
*
* Applications should not handle this signal.
*/
signals[FLUSH_EVENTS] =
g_signal_new (g_intern_static_string ("flush-events"),
GDK_TYPE_FRAME_CLOCK,
G_SIGNAL_RUN_LAST,
0,
NULL, NULL, NULL,
G_TYPE_NONE, 0);
/**
* GdkFrameClock::before-paint:
* @clock: the frame clock emitting the signal
*
* Begins processing of the frame.
*
* Applications should generally not handle this signal.
*/
signals[BEFORE_PAINT] =
g_signal_new (g_intern_static_string ("before-paint"),
GDK_TYPE_FRAME_CLOCK,
G_SIGNAL_RUN_LAST,
0,
NULL, NULL, NULL,
G_TYPE_NONE, 0);
/**
* GdkFrameClock::update:
* @clock: the frame clock emitting the signal
*
* Emitted as the first step of toolkit and application processing
* of the frame.
*
* Animations should be updated using [method@Gdk.FrameClock.get_frame_time].
* Applications can connect directly to this signal, or use
* [method@Gtk.Widget.add_tick_callback] as a more convenient interface.
*/
signals[UPDATE] =
g_signal_new (g_intern_static_string ("update"),
GDK_TYPE_FRAME_CLOCK,
G_SIGNAL_RUN_LAST,
0,
NULL, NULL, NULL,
G_TYPE_NONE, 0);
/**
* GdkFrameClock::layout:
* @clock: the frame clock emitting the signal
*
* Emitted as the second step of toolkit and application processing
* of the frame.
*
* Any work to update sizes and positions of application elements
* should be performed. GTK normally handles this internally.
*/
signals[LAYOUT] =
g_signal_new (g_intern_static_string ("layout"),
GDK_TYPE_FRAME_CLOCK,
G_SIGNAL_RUN_LAST,
0,
NULL, NULL, NULL,
G_TYPE_NONE, 0);
/**
* GdkFrameClock::paint:
* @clock: the frame clock emitting the signal
*
* Emitted as the third step of toolkit and application processing
* of the frame.
*
* The frame is repainted. GDK normally handles this internally and
* emits [signal@Gdk.Surface::render] signals which are turned into
* [signal@Gtk.Widget::snapshot] signals by GTK.
*/
signals[PAINT] =
g_signal_new (g_intern_static_string ("paint"),
GDK_TYPE_FRAME_CLOCK,
G_SIGNAL_RUN_LAST,
0,
NULL, NULL, NULL,
G_TYPE_NONE, 0);
/**
* GdkFrameClock::after-paint:
* @clock: the frame clock emitting the signal
*
* This signal ends processing of the frame.
*
* Applications should generally not handle this signal.
*/
signals[AFTER_PAINT] =
g_signal_new (g_intern_static_string ("after-paint"),
GDK_TYPE_FRAME_CLOCK,
G_SIGNAL_RUN_LAST,
0,
NULL, NULL, NULL,
G_TYPE_NONE, 0);
/**
* GdkFrameClock::resume-events:
* @clock: the frame clock emitting the signal
*
* Emitted after processing of the frame is finished.
*
* This signal is handled internally by GTK to resume normal
* event processing. Applications should not handle this signal.
*/
signals[RESUME_EVENTS] =
g_signal_new (g_intern_static_string ("resume-events"),
GDK_TYPE_FRAME_CLOCK,
G_SIGNAL_RUN_LAST,
0,
NULL, NULL, NULL,
G_TYPE_NONE, 0);
}
static void
gdk_frame_clock_init (GdkFrameClock *clock)
{
GdkFrameClockPrivate *priv;
clock->priv = priv = gdk_frame_clock_get_instance_private (clock);
priv->frame_counter = -1;
priv->current = FRAME_HISTORY_MAX_LENGTH - 1;
if (fps_counter == 0)
fps_counter = gdk_profiler_define_counter ("fps", "Frames per Second");
}
/**
* gdk_frame_clock_get_frame_time:
* @frame_clock: a `GdkFrameClock`
*
* Gets the time that should currently be used for animations.
*
* Inside the processing of a frame, its the time used to compute the
* animation position of everything in a frame. Outside of a frame, it's
* the time of the conceptual “previous frame,” which may be either
* the actual previous frame time, or if thats too old, an updated
* time.
*
* Returns: a timestamp in microseconds, in the timescale of
* of g_get_monotonic_time().
*/
gint64
gdk_frame_clock_get_frame_time (GdkFrameClock *frame_clock)
{
g_return_val_if_fail (GDK_IS_FRAME_CLOCK (frame_clock), 0);
return GDK_FRAME_CLOCK_GET_CLASS (frame_clock)->get_frame_time (frame_clock);
}
/**
* gdk_frame_clock_request_phase:
* @frame_clock: a `GdkFrameClock`
* @phase: the phase that is requested
*
* Asks the frame clock to run a particular phase.
*
* The signal corresponding the requested phase will be emitted the next
* time the frame clock processes. Multiple calls to
* gdk_frame_clock_request_phase() will be combined together
* and only one frame processed. If you are displaying animated
* content and want to continually request the
* %GDK_FRAME_CLOCK_PHASE_UPDATE phase for a period of time,
* you should use [method@Gdk.FrameClock.begin_updating] instead,
* since this allows GTK to adjust system parameters to get maximally
* smooth animations.
*/
void
gdk_frame_clock_request_phase (GdkFrameClock *frame_clock,
GdkFrameClockPhase phase)
{
g_return_if_fail (GDK_IS_FRAME_CLOCK (frame_clock));
GDK_FRAME_CLOCK_GET_CLASS (frame_clock)->request_phase (frame_clock, phase);
}
/**
* gdk_frame_clock_begin_updating:
* @frame_clock: a `GdkFrameClock`
*
* Starts updates for an animation.
*
* Until a matching call to [method@Gdk.FrameClock.end_updating] is made,
* the frame clock will continually request a new frame with the
* %GDK_FRAME_CLOCK_PHASE_UPDATE phase. This function may be called multiple
* times and frames will be requested until gdk_frame_clock_end_updating()
* is called the same number of times.
*/
void
gdk_frame_clock_begin_updating (GdkFrameClock *frame_clock)
{
g_return_if_fail (GDK_IS_FRAME_CLOCK (frame_clock));
GDK_FRAME_CLOCK_GET_CLASS (frame_clock)->begin_updating (frame_clock);
}
/**
* gdk_frame_clock_end_updating:
* @frame_clock: a `GdkFrameClock`
*
* Stops updates for an animation.
*
* See the documentation for [method@Gdk.FrameClock.begin_updating].
*/
void
gdk_frame_clock_end_updating (GdkFrameClock *frame_clock)
{
g_return_if_fail (GDK_IS_FRAME_CLOCK (frame_clock));
GDK_FRAME_CLOCK_GET_CLASS (frame_clock)->end_updating (frame_clock);
}
static void
_gdk_frame_clock_freeze (GdkFrameClock *clock)
{
g_return_if_fail (GDK_IS_FRAME_CLOCK (clock));
GDK_FRAME_CLOCK_GET_CLASS (clock)->freeze (clock);
}
static void
_gdk_frame_clock_thaw (GdkFrameClock *clock)
{
g_return_if_fail (GDK_IS_FRAME_CLOCK (clock));
GDK_FRAME_CLOCK_GET_CLASS (clock)->thaw (clock);
}
void
_gdk_frame_clock_inhibit_freeze (GdkFrameClock *clock)
{
GdkFrameClockPrivate *priv;
g_return_if_fail (GDK_IS_FRAME_CLOCK (clock));
priv = clock->priv;
priv->n_freeze_inhibitors++;
if (priv->n_freeze_inhibitors == 1)
_gdk_frame_clock_thaw (clock);
}
void
_gdk_frame_clock_uninhibit_freeze (GdkFrameClock *clock)
{
GdkFrameClockPrivate *priv;
g_return_if_fail (GDK_IS_FRAME_CLOCK (clock));
priv = clock->priv;
priv->n_freeze_inhibitors--;
if (priv->n_freeze_inhibitors == 0)
_gdk_frame_clock_freeze (clock);
}
/**
* gdk_frame_clock_get_frame_counter:
* @frame_clock: a `GdkFrameClock`
*
* `GdkFrameClock` maintains a 64-bit counter that increments for
* each frame drawn.
*
* Returns: inside frame processing, the value of the frame counter
* for the current frame. Outside of frame processing, the frame
* counter for the last frame.
*/
gint64
gdk_frame_clock_get_frame_counter (GdkFrameClock *frame_clock)
{
GdkFrameClockPrivate *priv;
g_return_val_if_fail (GDK_IS_FRAME_CLOCK (frame_clock), 0);
priv = frame_clock->priv;
return priv->frame_counter;
}
/**
* gdk_frame_clock_get_history_start:
* @frame_clock: a `GdkFrameClock`
*
* Returns the frame counter for the oldest frame available in history.
*
* `GdkFrameClock` internally keeps a history of `GdkFrameTimings`
* objects for recent frames that can be retrieved with
* [method@Gdk.FrameClock.get_timings]. The set of stored frames
* is the set from the counter values given by
* [method@Gdk.FrameClock.get_history_start] and
* [method@Gdk.FrameClock.get_frame_counter], inclusive.
*
* Returns: the frame counter value for the oldest frame
* that is available in the internal frame history of the
* `GdkFrameClock`
*/
gint64
gdk_frame_clock_get_history_start (GdkFrameClock *frame_clock)
{
GdkFrameClockPrivate *priv;
g_return_val_if_fail (GDK_IS_FRAME_CLOCK (frame_clock), 0);
priv = frame_clock->priv;
return priv->frame_counter + 1 - priv->n_timings;
}
void
_gdk_frame_clock_begin_frame (GdkFrameClock *frame_clock)
{
GdkFrameClockPrivate *priv;
g_return_if_fail (GDK_IS_FRAME_CLOCK (frame_clock));
priv = frame_clock->priv;
priv->frame_counter++;
priv->current = (priv->current + 1) % FRAME_HISTORY_MAX_LENGTH;
/* Try to steal the previous frame timing instead of discarding
* and allocating a new one.
*/
if G_LIKELY (priv->n_timings == FRAME_HISTORY_MAX_LENGTH &&
_gdk_frame_timings_steal (priv->timings[priv->current],
priv->frame_counter))
return;
if (priv->n_timings < FRAME_HISTORY_MAX_LENGTH)
priv->n_timings++;
else
gdk_frame_timings_unref (priv->timings[priv->current]);
priv->timings[priv->current] = _gdk_frame_timings_new (priv->frame_counter);
}
/**
* gdk_frame_clock_get_timings:
* @frame_clock: a `GdkFrameClock`
* @frame_counter: the frame counter value identifying the frame to
* be received
*
* Retrieves a `GdkFrameTimings` object holding timing information
* for the current frame or a recent frame.
*
* The `GdkFrameTimings` object may not yet be complete: see
* [method@Gdk.FrameTimings.get_complete].
*
* Returns: (nullable) (transfer none): the `GdkFrameTimings` object
* for the specified frame, or %NULL if it is not available. See
* [method@Gdk.FrameClock.get_history_start].
*/
GdkFrameTimings *
gdk_frame_clock_get_timings (GdkFrameClock *frame_clock,
gint64 frame_counter)
{
GdkFrameClockPrivate *priv;
int pos;
g_return_val_if_fail (GDK_IS_FRAME_CLOCK (frame_clock), NULL);
priv = frame_clock->priv;
if (frame_counter > priv->frame_counter)
return NULL;
if (frame_counter <= priv->frame_counter - priv->n_timings)
return NULL;
pos = (priv->current - (priv->frame_counter - frame_counter) + FRAME_HISTORY_MAX_LENGTH) % FRAME_HISTORY_MAX_LENGTH;
return priv->timings[pos];
}
/**
* gdk_frame_clock_get_current_timings:
* @frame_clock: a `GdkFrameClock`
*
* Gets the frame timings for the current frame.
*
* Returns: (nullable) (transfer none): the `GdkFrameTimings` for the
* frame currently being processed, or even no frame is being
* processed, for the previous frame. Before any frames have been
* processed, returns %NULL.
*/
GdkFrameTimings *
gdk_frame_clock_get_current_timings (GdkFrameClock *frame_clock)
{
GdkFrameClockPrivate *priv;
g_return_val_if_fail (GDK_IS_FRAME_CLOCK (frame_clock), 0);
priv = frame_clock->priv;
return gdk_frame_clock_get_timings (frame_clock, priv->frame_counter);
}
#ifdef G_ENABLE_DEBUG
void
_gdk_frame_clock_debug_print_timings (GdkFrameClock *clock,
GdkFrameTimings *timings)
{
GString *str;
gint64 previous_frame_time = 0;
gint64 previous_smoothed_frame_time = 0;
GdkFrameTimings *previous_timings = gdk_frame_clock_get_timings (clock,
timings->frame_counter - 1);
if (previous_timings != NULL)
{
previous_frame_time = previous_timings->frame_time;
previous_smoothed_frame_time = previous_timings->smoothed_frame_time;
}
str = g_string_new ("");
g_string_append_printf (str, "%5" G_GINT64_FORMAT ":", timings->frame_counter);
if (previous_frame_time != 0)
{
g_string_append_printf (str, " interval=%-4.1f", (timings->frame_time - previous_frame_time) / 1000.);
g_string_append_printf (str, timings->slept_before ? " (sleep)" : " ");
g_string_append_printf (str, " smoothed=%4.1f / %-4.1f",
(timings->smoothed_frame_time - timings->frame_time) / 1000.,
(timings->smoothed_frame_time - previous_smoothed_frame_time) / 1000.);
}
if (timings->layout_start_time != 0)
g_string_append_printf (str, " layout_start=%-4.1f", (timings->layout_start_time - timings->frame_time) / 1000.);
if (timings->paint_start_time != 0)
g_string_append_printf (str, " paint_start=%-4.1f", (timings->paint_start_time - timings->frame_time) / 1000.);
if (timings->frame_end_time != 0)
g_string_append_printf (str, " frame_end=%-4.1f", (timings->frame_end_time - timings->frame_time) / 1000.);
if (timings->drawn_time != 0)
g_string_append_printf (str, " drawn=%-4.1f", (timings->drawn_time - timings->frame_time) / 1000.);
if (timings->presentation_time != 0)
g_string_append_printf (str, " present=%-4.1f", (timings->presentation_time - timings->frame_time) / 1000.);
if (timings->predicted_presentation_time != 0)
g_string_append_printf (str, " predicted=%-4.1f", (timings->predicted_presentation_time - timings->frame_time) / 1000.);
if (timings->refresh_interval != 0)
g_string_append_printf (str, " refresh_interval=%-4.1f", timings->refresh_interval / 1000.);
g_message ("%s", str->str);
g_string_free (str, TRUE);
}
#endif /* G_ENABLE_DEBUG */
#define DEFAULT_REFRESH_INTERVAL 16667 /* 16.7ms (1/60th second) */
#define MAX_HISTORY_AGE 150000 /* 150ms */
/**
* gdk_frame_clock_get_refresh_info:
* @frame_clock: a `GdkFrameClock`
* @base_time: base time for determining a presentaton time
* @refresh_interval_return: (out) (optional): a location to store the
* determined refresh interval, or %NULL. A default refresh interval of
* 1/60th of a second will be stored if no history is present.
* @presentation_time_return: (out): a location to store the next
* candidate presentation time after the given base time.
* 0 will be will be stored if no history is present.
*
* Predicts a presentation time, based on history.
*
* Using the frame history stored in the frame clock, finds the last
* known presentation time and refresh interval, and assuming that
* presentation times are separated by the refresh interval,
* predicts a presentation time that is a multiple of the refresh
* interval after the last presentation time, and later than @base_time.
*/
void
gdk_frame_clock_get_refresh_info (GdkFrameClock *frame_clock,
gint64 base_time,
gint64 *refresh_interval_return,
gint64 *presentation_time_return)
{
gint64 frame_counter;
gint64 default_refresh_interval = DEFAULT_REFRESH_INTERVAL;
g_return_if_fail (GDK_IS_FRAME_CLOCK (frame_clock));
frame_counter = gdk_frame_clock_get_frame_counter (frame_clock);
while (TRUE)
{
GdkFrameTimings *timings = gdk_frame_clock_get_timings (frame_clock, frame_counter);
gint64 presentation_time;
gint64 refresh_interval;
if (timings == NULL)
break;
refresh_interval = timings->refresh_interval;
presentation_time = timings->presentation_time;
if (refresh_interval == 0)
refresh_interval = default_refresh_interval;
else
default_refresh_interval = refresh_interval;
if (presentation_time != 0)
{
if (presentation_time > base_time - MAX_HISTORY_AGE &&
presentation_time_return)
{
if (refresh_interval_return)
*refresh_interval_return = refresh_interval;
while (presentation_time < base_time)
presentation_time += refresh_interval;
if (presentation_time_return)
*presentation_time_return = presentation_time;
return;
}
break;
}
frame_counter--;
}
if (presentation_time_return)
*presentation_time_return = 0;
if (refresh_interval_return)
*refresh_interval_return = default_refresh_interval;
}
void
_gdk_frame_clock_emit_flush_events (GdkFrameClock *frame_clock)
{
g_signal_emit (frame_clock, signals[FLUSH_EVENTS], 0);
}
void
_gdk_frame_clock_emit_before_paint (GdkFrameClock *frame_clock)
{
g_signal_emit (frame_clock, signals[BEFORE_PAINT], 0);
}
void
_gdk_frame_clock_emit_update (GdkFrameClock *frame_clock)
{
gint64 before G_GNUC_UNUSED;
before = GDK_PROFILER_CURRENT_TIME;
g_signal_emit (frame_clock, signals[UPDATE], 0);
gdk_profiler_end_mark (before, "frameclock update", NULL);
}
void
_gdk_frame_clock_emit_layout (GdkFrameClock *frame_clock)
{
gint64 before G_GNUC_UNUSED;
before = GDK_PROFILER_CURRENT_TIME;
g_signal_emit (frame_clock, signals[LAYOUT], 0);
gdk_profiler_end_mark (before, "frameclock layout", NULL);
}
void
_gdk_frame_clock_emit_paint (GdkFrameClock *frame_clock)
{
gint64 before G_GNUC_UNUSED;
before = GDK_PROFILER_CURRENT_TIME;
g_signal_emit (frame_clock, signals[PAINT], 0);
gdk_profiler_end_mark (before, "frameclock paint", NULL);
}
void
_gdk_frame_clock_emit_after_paint (GdkFrameClock *frame_clock)
{
g_signal_emit (frame_clock, signals[AFTER_PAINT], 0);
}
void
_gdk_frame_clock_emit_resume_events (GdkFrameClock *frame_clock)
{
g_signal_emit (frame_clock, signals[RESUME_EVENTS], 0);
}
static gint64
guess_refresh_interval (GdkFrameClock *frame_clock)
{
gint64 interval;
gint64 i;
interval = G_MAXINT64;
for (i = gdk_frame_clock_get_history_start (frame_clock);
i < gdk_frame_clock_get_frame_counter (frame_clock);
i++)
{
GdkFrameTimings *t, *before;
gint64 ts, before_ts;
t = gdk_frame_clock_get_timings (frame_clock, i);
before = gdk_frame_clock_get_timings (frame_clock, i - 1);
if (t == NULL || before == NULL)
continue;
ts = gdk_frame_timings_get_frame_time (t);
before_ts = gdk_frame_timings_get_frame_time (before);
if (ts == 0 || before_ts == 0)
continue;
interval = MIN (interval, ts - before_ts);
}
if (interval == G_MAXINT64)
return 0;
return interval;
}
/**
* gdk_frame_clock_get_fps:
* @frame_clock: a `GdkFrameClock`
*
* Calculates the current frames-per-second, based on the
* frame timings of @frame_clock.
*
* Returns: the current fps, as a `double`
*/
double
gdk_frame_clock_get_fps (GdkFrameClock *frame_clock)
{
GdkFrameTimings *start, *end;
gint64 start_counter, end_counter;
gint64 start_timestamp, end_timestamp;
gint64 interval;
start_counter = gdk_frame_clock_get_history_start (frame_clock);
end_counter = gdk_frame_clock_get_frame_counter (frame_clock);
start = gdk_frame_clock_get_timings (frame_clock, start_counter);
for (end = gdk_frame_clock_get_timings (frame_clock, end_counter);
end_counter > start_counter && end != NULL && !gdk_frame_timings_get_complete (end);
end = gdk_frame_clock_get_timings (frame_clock, end_counter))
end_counter--;
if (end_counter - start_counter < 4)
return 0.0;
start_timestamp = gdk_frame_timings_get_presentation_time (start);
end_timestamp = gdk_frame_timings_get_presentation_time (end);
if (start_timestamp == 0 || end_timestamp == 0)
{
start_timestamp = gdk_frame_timings_get_frame_time (start);
end_timestamp = gdk_frame_timings_get_frame_time (end);
}
interval = gdk_frame_timings_get_refresh_interval (end);
if (interval == 0)
{
interval = guess_refresh_interval (frame_clock);
if (interval == 0)
return 0.0;
}
return ((double) end_counter - start_counter) * G_USEC_PER_SEC / (end_timestamp - start_timestamp);
}
void
_gdk_frame_clock_add_timings_to_profiler (GdkFrameClock *clock,
GdkFrameTimings *timings)
{
if (timings->drawn_time != 0)
{
gdk_profiler_add_mark (1000 * timings->drawn_time, 0, "drawn window", NULL);
}
if (timings->presentation_time != 0)
{
gdk_profiler_add_mark (1000 * timings->presentation_time, 0, "presented window", NULL);
}
gdk_profiler_set_counter (fps_counter, gdk_frame_clock_get_fps (clock));
}